1. Field of the Invention
This invention generally relates to a die structure and a die connecting method. More particularly, this invention relates to a die structure for electrically coupling to a circuit board and a die connecting method using the same.
2. Description of the Prior Art
Among the chip-packaging technologies, flip-chip interconnect technology (FC) is generally used. In the flip-chip interconnect technology, a plurality of die pads are disposed in area array on an active surface of the die, wherein a bump structure 80 shown in FIG. 1A is formed on the die pad. After flipping the die 20, the bump structure 80 on the die 20 is coupled to a circuit 70 in the circuit board 60 shown in FIG. 1B via a conducting material 11. Afterward the die 20 is coupled to the circuit board 60 by means of the bump structure 80 and can be further electrically coupled to an external electronic device via the circuit board, as shown in FIG. 1C.
However, the conventional bump structure 80 is made up by a copper block 10 and a gold layer 40 covered thereon. It is difficult to reduce the manufacture cost due to the high price of the gold material. On the other hand, to electrically connect the bump structure 80 to the circuit board 60, a tin layer 33 must cover on the conducting material 11 for soldering with the gold layer 40. Since the tin layer 33 covering on the conducting material 11 has a certain thickness, the distance between the conducting materials 11 must be increased to prevent short-circuit. In other words, the number of the conducting materials 11 and the dies 20 that may be disposed in a given area is therefore decreased.